What is Blockly

Blockly is a web library that lets you add a blocks-based code editor to your app. The editor uses puzzle-piece like blocks to represent code concepts like variables, logical expressions, loops, and more. It lets users program without having to worry about syntax or the intimidation of the command line.

Note: Blockly is for developers, Blockly apps are for learners. If you're here to use apps rather than build them, check out the list on our home page.

Breaking it down further, you can think of Blockly in two ways:

1. Like a fun puzzle-piece UI.
2. Like a fancy string builder.

You define the puzzle connections and input fields, and then Blockly handles the complicated rendering, dragging, and connecting of them.

You define the string (usually code) that gets generated for each block, and then Blockly handles concatenating whole strings of blocks. What you do with that result is up to you. You can do anything from solving a maze, to animating a character, to analyzing some data.

Blockly lets you focus on applying blocks to your domain without worrying about the details of how blocks work. For more information see Why Blockly?